Improvement in safety  door-key guaed



W. K. MARVIN.

Safety Door Key Guard.

I Patented May 5, 1868.

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WALTER. K. MARVIN, 0F- NEW-YORK, N, Y.

Letters Patent N01 77,633, dated May 5, 1868 mrnovsn'snrm SAFETY noon-KEY GUARD.

TO WHOM IT MAY CONCERN p v Be it known that I, WALTER, K. MARVLN, ot-New York, in the county and State of; New'York, have invehted a certain new and improved- Device for FasteningKeys in Locks and I hereby declare the-following to be a full, cleaigand exact description of the same, reference being had to the accompanying drawings, in which-F.

Figure 1 is a perspective view of a door-lock, with mytimproved. key fasteuing1device applied. Figure 2 is a transverse vertical section'of the same, through the key-hole dud key. It is well known that ordinary locks, on s'-treet,' or chamber, or otherdoo'rs, arefrequently openedfrom the outside, either by grasping the end of the door-key, which istinserted in the lock,with a suitable instrument, by which the key is then turned .or operated so as to draw hack the bolt, or byjurning and pushing out the key from the key-hole, so as to make way 'for a loclbpickingdevice.

1 The object of any invention is to remedy this eiril, or, in other words, to'secureand hold in placethe'key in such manner that it can neither be forced out from the key-hole nor operated in anylmnnner from-the outside, on from the side of the door opposite that in which the key is inserted. v

To this end, my invention consists essentially of a key-fastener, composed of a. plat e'or escutchepn, hinged to the door or other part, in properrelation to the key, as hereinafter described, and carrying a slide or tongue- (piece, capable of being projected into or retractedfrom the key-handle, and a spring for holding the said tongue.

in-position when projected into the said key-handle. I I V p i p To enable others skilled'in-the art to understandand use my invention, I will now procced todscribe the maunerin which the same is or maybe carried into effect, by reference to the accompanying drawings;

The key-fastehing device, there-shown; :onsists'of the .plat'e A, in' onc face of which a recessis formed, running lengthwise of theplate. In this recess is held a sliding plate or tongue, B, which'fitsin dovetailed ways a, formed in the sides of the recess, 7

Below the tongue, which, when not projected fro h the main plate, fits a little over one-halfthe recess, is

secured aplate or flat metal spring, 0, and at the point-where it is. situated the recess is made alittle deeper, so that, when the slide B is retracted, the spring niay be-pressed back and covered by,the lower part of the slide, which passes over it.

, The spring is secured to the plate A by its lower end, aslshown in fig. 2,,while its npperior free end projects,

froni the recess, so as to bear up under the end of the slide. when the' latter is projected from the plate, as rep;

"resented in thefigurc referred to.

1 ,The slidingmovemcnt of the tongue .B islimitod by means of a pin or stud, 6, which projects from the hottom of the recessin the plate A, and takes into a slot, 0, formed in the contiguous face ofthe tongue,

The main-plate Ais'hingedor pivoted to-a holding-plate, D, which, as shown'in the drawings, is heldin proper position, upon the door or other place, by means-of screws, or other suitahle means.

l The manner in which th'e device is used, in connectionwith a lock and key, is as follows. Let it he supposed thatE represents a door 'F the key, f the keyhole, andh theholt' of clock of ordinary or suitahle'construction. The holding-plate, D, of the fastener is applied and secured 'tothe door in such position that when the plate A is swung upon its pivot or hinge towards the key F, the endof said plate should be nearly or quite in co ntactwith the loop or handle, 7:, of the key. ,When the fasteneris thus attached to the door, the key, what ever be'the position of the bolt k, can at oncebe secured against alhdanger of being pushed from or turned in the lock. All that is needed to efi'ect this is to raise the fastener from the position indicated in red .lines'in fig". 1,].to that indicated in black-lines, the key being turned in such manner that the loops inithe handle is will be turned toward the fastener, in which position the handle'will bear against the top of the plate A. The tongue or slide, B, is now-projected from the plate through the' handle, whereit is-held by meaus'of the spring 0, as

indicated in fig. 2. The key, in this simple and efl'ective manner, is-securely held in position, and can-be neither pushed out from the key-hole'nor turned sons to operate the lock.

' the drawing.

When it isdesired toreleese the key, the spring 0 is pressed back, the slide B is drawn or pushed down, and the fastener is then'swnng beck to the ,position indieated'in red lines, fig. 1.

In order to facilitate 'the moving of the slide, a thlimh or finger-notch, on, may be formed in it, as shown in A fastening-device thus made can be applied to 'any and all doors without trouble,'and the advantages resulting fromits use are too manifest to need necitel.

Having, therefore, described my invention, and the manner in which the smne is or may be carried into effect, what I claim, and de'sire'to secure by Letters Patent, i s-- I The combination of the plete A with n siide'or tongue, niounted in or upon said plate, and n spring to hold said tongne in position, snbstantiallyin the manner desci'ibed, the whole constituting a. key-fastening device, hinged to the door or other part where the key is loc ated, so as to operate in eonnection with the said key, substelntially a's and for thepurposes show1i.and specified. I

In testimony whepeof, I heversigned my name to this specification before two subscribing witnesses.

WALTER K. MARVIN.

- Witn esses J. B. Norms, A. KAYSLES. 

